SmogRank / History / Country race
Countries, worst air first, day by day
Each country's typical measured city over the 30 days to every day since January 2023, worst first. Press Play to watch the order change, or drag the slider to any day.
The worst countries for PM2.5 over the 7 days to 25 Jun 2023: Pakistan 52.1 µg/m³, Chile 37.2 µg/m³ and India 31.0 µg/m³.
- 1Pakistan4 cities52.1
- 2Chile44 cities37.2
- 3India5 cities31.0
- 4China3 cities21.8
- 5Mexico15 cities17.6
- 6Slovakia25 cities14.6
- 7Malta4 cities14.1
- 8Czechia35 cities13.5
- 9Serbia3 cities13.4
- 10Hungary8 cities12.9
- 11Thailand11 cities12.8
- 12Greece8 cities12.4
- 13Lithuania4 cities12.3
- 14Italy32 cities11.9
- 15Singapore5 cities11.4
- 16Romania6 cities11.1
- 17Bulgaria6 cities10.9
- 18Belgium41 cities10.2
- 19Austria30 cities10.1
- 20Germany204 cities10.0
+ 11 more countries, 9.6 µg/m³ and below
- 24United States745 cities7.8
Not counted on this day, too few cities measured: Luxembourg since 24 Jun 2023, The Netherlands since 24 Jun 2023, Poland since 24 Jun 2023 and 7 more countries.
Countries counted each day
A country's number is its typical measured city: the median of its cities' means over the 30 days (a city needs 21 of them measured; 5 of 7 on the 7-day race), shown only with 3 such cities. A country whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air; "was" beside a city count marks a month after many cities joined or left. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.
Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites; we are building the readers for them. Most cities there are missing from this board, not clean. Why.